Electric-arc lamp.



No. 706,547. Patented Aug. l2, |902. F. A. GILBERT & E. o. LuNDl'N.

ELECTRIC ARC LAMP.

(Application filed. Mur. 24, 1898.)

(No Modal.)

M MM d@ UNITED STATES PATENT OEEIC FREDERICK A. GILBERT, OF BROOKLINE,AND EMIL O. LUNDIN, OF BEACH- MONT, MASSACHUSETTS, ASSIGNORS TO THEGENERAL ELECTRIC COM- PANY, A CORPORATION OF NEW YORK.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 706,547, dated August12, 1902.

.zi-@nanou inea March 24, 189e.

To (LZZ whom t may concern: 1

Be it known that we, FREDERICK A. GIL- BERT, of Brookline, county ofNorfolk, andl EMIL O. LUNDIN, 4of Beachmont, county of 5 Suffolk, Stateof Massachusetts, have invented an Improvement in Electric-Arc Lamps, ofwhich the following description, in connection with the accompanyingdrawings, is a specification, like letters onihe drawings repre- Iosenting like parts.

This invention relates to arc-lamps, having more especial reference tothat class of lam ps V in which carbon-rods are dispensed with.

The invention has for its particular obj ect I 5 the production ofsimple and highly-effective means for making electrical contacty at alltimes between the upper carbon and the controlling means therefor,obviating the use of resilient or spring contacts, with their rapid 2odeterioration.

Figure l represents in elevation an arclamp, partly broken out andembodying our invention, the outer globe and the lamp-case being shownin section. Fig. 2 is an enlarged longitudinal sectional view of thetubular clutch-actuator for the upper carbon, the carbon-carrier, andthe contact device, the latter being shown in section. Fig. 3 is a likeview of a modified form of our invention 5 and 3o Fig. 4 is an underside view of the contactsupport, with the contact members spread apart.Y

Referring to Fig. l, the open upper body portion A of the frame, havinga base A', supporting the usual serieswound and shunt coils, the latterbeing shown at C', the outer globe GX, its supporting-socket A, theinner globe G, the clutch mechanism h b4 b5 b'', and the 'tubular clutchactuator B, extended 4o through the open body A and contacting with thebase A', which passes freely therethrough, and the resistance R R', rnaybe and are all substantially as shown in a patent granted to us May 10,1898, No. 603,630. In the construction therein shown the contact devicefor the upper carbon L comprised a series of gravityactuated rockingcontact members mounted in a suitable holder attached to said actuator.

We have improved the construction of the Serial No. 674,983. (No model.)

contact device between the upper carbon and the clutch-actuator B in ourpresent invention, simplifying the same and attaining greatereffectiveness in its operation.

Referring to Figs. 1 and 2, the upper-car- 55 bon carrier is shown as ashort Inetal tube (L, preferably longitudinally slotted at its lower endat a to embrace and hold frictionally the upper end of the carbon L'.This carrier slides loosely and freely in the tubular clutch- 6oactuator B, electrically connected through the metal body of the lampwith the line-wire l, as in the patent above referred to, and in orderto insure eective contact at all times between the tube B andcarbon-carrier d the latter is shown as provided with a series of metalcontact members d, pivotally mounted at their upper ends at d on a metalcap (ZX, secured in the top of the carrier. Foul` contact members d areshown, arranged in radial 7o slots d2 in the cap, which latter isrecessed between theslots to permit the ready insertion of thepivot-pins CZ, the contact members projecting through longitudinal slotsa2 in the carrier to engage the inner surface of the tube B,the outeredges of said members d being preferably flattened, as at d, to insure alonger engaging surface. The inner edges of the contact members areconcaved, as at di, for a purpose to be described 8o and their lowerends are extended, as at d5, below the bottoms ofthe slots a2 to act asstops and limit the outward movement of the members. The contactinembersthus arranged form a cage, as it were, in which is loosely held aspreader f, shown as a metal sphere, which rests on the concave seatsd4, said seats inclining down and inward toward the cen- AVter of thecarrier, the tendency of the spreader being to separate or push thecontact mem- 9o bers d outward and maintain them against the walls ofthe clutch-actuator B. In order to increase this action of the spreader,We prefer to attach a weight fx thereto bya metallic connection f', sothat the current will pass 95 from the contact members (t to thespreader and thence to the weight, and as the latter is somewhat smallerthan the internal diameter of the carrier we prefer to electricallyconnect the weight to the carrier by a iiexible Ioo Wire fi, attached toa metal plugfg, secured in the carrier below the Weight. Current canalso pass to the carrier from the contact members by the cap (ZX andthence to the carbon L by the metallic Walls ot" the carrier, and itwill be obvious that anumberof contact members will be at all times inengagement with the ltube B, securing a highly-effective electricalContact7 While not interfering with the movement of the carbon-carrieras the carbon is fed. By this construction all spring action of thecontact members is obviated, the latter being made as rigid metal piecesper se, and consequently the rapid deterioration of spring-contacts bythe electric current is completely overcome, while at the same time thecontact provided by our invention is as effective, if indeed not greatlysuperior to, as the contact attained by spring-contacts when entirelynew and active.

By a slight modification (shown in Fi.

the same results are attained, the weight being replaced by a spring,which latter, however, is by suitable insulation protected from theaction of the current.

elow the contact members d a plug 7i is fixed in the carriera, and acontractile spring s is connected at its ends to the spreaderf and plugh, either or both of which are made of insulating material,so that thecurrent cannot pass through the spring and cause it to lose its life.

In either construction the movement of the spreader longitudinally ofthe carrier and toward the separable ends of the contact members deffects the same result-viz., a positive and continuous lateralseparation or spreading of said members.

Our invention is not restricted to the precise construction andarrangement of parts as herein shown, as obviously the same may bevaried or rearranged without departing from the spirit and scope of theinvention.

The currentin the lamp shown herein passes from one carbon to the other,forming the arc when the lamp is burning, and from the lower carbon L byinsulated Wire ZX to one end of the series-wound coil, through thelatter and back to line at ZC Having fully described our invention, whatWe claim as new, and desire to secure by Letters Patent, is

l. An electric-arclamp provided withacontact device for the movablecarbon, means for connecting and disconnecting the same from thecarbon,and a rigid leveryieldingly mounted on the contact device andeffecting a sliding frictional contact between the carbon-follower andthe circuit-terminal.

2. An arc-lamp provided with a device for maintaining contact betweenthe movable carbon and a circuit-terminal, means permitting the carbonto be connected and disconnected therefrom, and a plurality of leversmounted on one of the parts and held in elastic or yielding frictionalengagement with the other part.

reas-lv 3. A contact device for the movable carbon of an arc-lamp,comprising a support, a plurality of independently-movable,laterallyseparable contact members mounted thereon and electrically connectedwith the carbon, said members having elongated contact-faces andinterior cam portions, and means to engage said cam portions of thecontact members and positively spread them laterally into operativeposition.

A contact device for the movable carbon of an arc-lamp, comprising asupport, a plurality of independently-movable,laterally separablecontact members mounted thereon and electrically connected with thecarbon, said members having elongated contact-faces and interior camportions, a spreader inclosed and supported by the contact members, andmeans to move said spreader to positively separate and maintain thecontact members in operative position.

5. A contact device for the movable carbon of an electric lamp,comprising a plurality of iniiexible, separable contact-leverselectrically connected and bodily movable with thc carbon and means topositively separate or laterally extend the free ends of said levers inoperative position.

G. In an arc-lamp, a carbon-carrier, a tubular metallic guide therefor,a plurality ofseparable contact-levers mounted on the carrier inelectrical connection with the carbon, and means to positively separateor laterally eX- tend the free ends of said levers and maintain themoperatively in contact with the guide.

7. ln an arc-lamp, a carbon-carrier, a metallic tube through which ittravels and in the lamp-circuit, a plurality of separable contactleversmounted on the carrier and electrically connected with the carbon, and aspreader to act upon the lever-arms and positively separate or laterallyextend them and maintain them in operative contact with the tube.

8., In an arc-lamp, a metallic tube in the lamp-circuit and within whichthe movable carbon travels, a carbon-carrier, pivoted contact-levers inelectrical connection with the carbon, and means to positively engageand move said contact-levers into operative position and to maint-ainthem in yielding sliding engagement with said tube.

9. In an arc-lamp, a metallic carbon-carrier having side openingstherein, a plurality of depending contact members pivotally mounted onthe carrier, a spreader Within and su pported by the said members, andmeans to move said spreader to positively separate said contact membersand maintain them in operative position projecting laterally through theopenings in the carrier.

lO. A contact device for the movable carbon of an arc-lamp, com prisingaplurality of movable contact-levers electricallyconnected with thecarbon, and means to positively maintain said contact-levers inoperative position.

1l. In an arc-lamp, a carbon-carrier, atubular metallic guide therefor,a plurality of mov- IOO IIO

able contact-levers mounted on the carrier in electrical connection withthe carbon, and means to positively maintain said levers in operativeContact with the guide.

l2. In an eleotrie-are lamp, a movable carbon, a tube wherein the sameis adapted to slide, a Contact for the movable carbon eomprising aseries of arms bent inwardly and each pivoted at one end in the holderfor the carbon, and means surrounded by said arms for maintaining thesame in expanded position.

I3. In an eleetrie-are lamp, a Contact for the upper carbon com prisinga series of arms bent FREDERICK A. GILBERT. EMIL O. LUNDIN.

Witnesses:

JOHN OOUPER EDWARDS, L. M. WALLACE.

